Apple runs App Store with 78% profit margin, according to court testimony

It is an open secret that the App Store is a huge revenue and profit driver for Apple but to date Apple has not disclosed figures that break out exactly how profitable the App Store is. Apple has previously told senators that its business does not calculate profit and loss for individual products and services.
However, new court testimony in the Apple-vs-Epic trial (which commences next week) seemingly reveals a number that Apple has tried to keep quiet. Via Bloomberg, the App Store ran at a 78